Some embodiments relate to drones, and particularly to micro-drones with beating wings that are capable of stationary flight and of actuation mechanisms allowing these stationary flights.
Related art micro-drones with beating wings exist. For many of them, actuation mechanisms have been developed for the purpose of allowing stationary flight.
In particular, micro-drones flying by using resonating mechanisms that actuate a pair of beating wings of this micro-drone have been proposed. These mechanisms use two DC motors each having a rotor axis to which one of the wings is directly attached. For each motor, a coil spring is linked on one side to a wing and on the other to the body of the motor. Each motor is underpowered so as to beat the wings at the resonant frequency of the mechanical system driven by this motor, in particular the wing and the spring that are linked to this motor.
The advantage of such a mechanism is that it allows the pitch and the roll to be controlled simply by controlling the amplitude of the beating motion. This therefore allows the number of actuators to be decreased in comparison with systems that use the deformation and the specific orientation of the wings to control the pitch and the roll.
In addition, by virtue of the resonance of the system, this mechanism makes it possible to avoid the energy expenditure desired in this embodiment to reverse the angular speed of the wing, the inertia of which is non-negligible. All or most of the power delivered by the motor can thus be used to compensate for the damping of the motion due to aerodynamic forces.